How to visit Slovenia’s Postojna Cave & Predjama Castle

Last updated on May 25th, 2026

One of the most popular day trips from Ljubljana, Slovenia is a visit to Postojna Cave and Predjama Castle. Located less than an hour from the city, these two sites make for a fun half day adventure filled with history, medieval vibes, and geological wonders.

And if you’re looking to visit Postojna Cave and Predjama Castle for yourself, we’re sharing how to visit both on the same day, different tour options, plus what to expect at each!

Predjama Castle | Best day trips from Ljubljana, Slovenia

Looking for more things to do in Slovenia?

What are Postojna Cave and Predjama Castle?

The Postojna Cave and Predjama Castle are two of Slovenia’s top things to do. And after road tripping around most of the country, we totally agree that they should be a part of your Slovenia itinerary. Before we dive into how to visit them, let’s take a quick look at what they even are!

Postojna Cave

Slovenia is home to over 14,000 caves and Postojna Cave is the most popular of them all! The cave stretches 24 kilometers (~15 miles), with a maximum depth of 120 meters (394 feet), which is equivalent to a 36 story building. It was created over millions of years by the Pivka River dissolving the limestone in the region’s Karst plateau. And it’s still changing today!

Predjama Castle

Predjama Castle is the largest cave castle in the world! This 800 year old castle is perched in the middle of a 123 meter (403 feet) high cliff, inside the mouth of a cave, and is unlike any castle we have ever seen!

It was originally constructed by the Patriarch of Aquileia, but in the 15th century, it came under the ownership of a knight named Erazem. Erazem was known for his rebellious stand against the Habsburgs, using the castle’s hidden tunnels to withstand sieges.

Unfortunately Erazem died by a shot from a cannon while on the toilet, which is a pretty crappy way to go if you ask us! And after his death in 1484, the castle changed hands many times and underwent several reconstructions, with its current appearance completed in the 16th century.

Pronunciation tip: You may notice a lot of Slovenian words have a “j” in them. This “j” is usually pronounced as more of a “y” sound. So Postojna is pronounced “post-oy-nah” and Predjama is pronounced “pred-yah-mah.”

How to get to Postojna Cave and Predjama Castle

Postojna Cave and Predjama Castle are located just under an hour southwest of Ljubljana, right by the town of Postojna. However, it’s important to know that they are not right next to each other.

Postojna Cave is the closer of the two attractions (45 minutes from Ljubljana), with Predjama Castle being located about 15 minutes further up the road from the cave. Getting to both attractions is pretty easy through your own car, public transportation, or a tour.

Car & campervan

Getting to Postojna Cave and Predjama Castle is a breeze by car or campervan! You will hop onto the A1 Motorway from Ljubljana, which is pretty much a straight shot to Postojna.

Once you’re there, there is ample paid parking for both attractions. Unfortunately your parking fee doesn’t cover both spots, so you will have to pay twice. Postojna Cave charges €6 for a car for the whole day, while Predjama Castle charges €3 per hour.

Since we were in a campervan, we had to pay €12 for each parking lot. From April to October you can also camp at Postojna Cave for the night in a campervan for €25 for 24 hours, which includes electricity hook ups, water, and sewage.

Important to know: If renting a car in Slovenia, you will need a vignette, which is a toll system that is required to drive highways in Slovenia. Also, make sure you have an IDP if traveling from another country (if required). For Americans, AAA sells these for $20 and it lasts a year.

Public Transportation from Ljubljana

If you want to visit by public transportation from Ljubljana, you can either take a train or bus.

Buses leave on the hour from Ljubljana and it takes about 40 minutes to get to the Postojna bus station in the town center. From there, you can either walk about 20 minutes to Postojna Cave or take a taxi.

To visit by train, it takes about 1 hour and 20 minutes. You can see the train schedule here or plug in the route on Google Maps. The train station is a bit further from the cave and takes about 25 minutes to walk there. So overall, the bus is the more efficient option.

Curious how to get between Postojna Cave and Predjama Castle without a car? During the summer months, a free shuttle bus runs between the two sites. However, it does run on a more limited schedule, so you will need to ensure you plan properly to not have to wait for a long time. You could also utilize this shuttle even if visiting by car, if you want to avoid paying for parking twice. Another option is to take a taxi from the cave to the castle, which you may be able to share with other travelers.

Tour from Ljubljana

If you’d like all the logistics taken care of for you, including pick up and drop off from Ljubljana, transportation to the cave and castle, and tickets for entry, we suggest booking this Postojna Cave and Predjama Castle tour. This will make visiting a breeze if you don’t have a car!

Want to save some money on this tour or experience? Join Tripadvisor Rewards to earn 5% Trip Cash on any hotel or experience booking made in their app, which can be applied to future in-app bookings!

How to get tickets to Postojna Cave and Predjama Castle

Tickets for Postojna Cave and Predjama Castle can be purchased online or in person at the Postojna Cave Park. Postojna Cave costs €32.90 per adult and Predjama Castle costs €21 per adult to visit. But if you plan to visit both, you can get a combo ticket, which is only €46.50.

We personally suggest booking online, as you will need to choose a timeslot (dateand time) for Postojna Cave. And some timeslots can sell out during peak season!

However, if your plans change, you are able to change your cave tour time up to 24 hours beforehand, free of charge. If you change within 24 hours it costs €2 per ticket and within 30 minutes of your tour time it will cost €5 per ticket. You do not need to book a timeslot for Predjama Castle and can arrive whenever you’d like!

Which should you visit first?

Postojna Cave | Best day trips from Ljubljana, Slovenia

You might read on other blogs and even the official website for Postojna Cave that you should visit Predjama Castle first and Postojna Cave second. But we suggest the opposite!

We think you should visit Postojna Cave first because you have to pick a timeslot, whereas you can enter Predjama Castle any time you like. If you visit Predjama Castle first, your visit will be limited by your cave entry time. So if you happen to take longer than planned, you may feel rushed to get to the cave. But if you visit Postojna Cave first, you can freely explore the castle without any time crunch.

We also suggest visiting earlier in the day to avoid the large tour groups that may arrive a bit later. By taking the first tour for Postojna Cave, we were able to easily find parking and then get to Predjama Castle before it was too busy.

What to expect on the Postojna Cave Tour

Postojna Cave at a glance

Cost: €32.90 per adult (cheaper with combo ticket)
Total length of time: 90 minutes
Timeslot required?: You are required to choose a timeslot for this tour. Make sure to arrive 30 minutes early.
Languages: Tours are offered in Slovenian, Italian, English or German, but they also have audio guides for a dozen other languages.
Difficulty: We felt that this was an easy tour, but you do have to walk 1 km (~0.6 mile) over 60 minutes. It is a very slow pace, but there are some inclines and declines to be aware of.

Train ride into the cave

The Postojna Cave tour starts out in a very exciting way…with a 15 minute train ride into the heart of the cave! Before we visited we assumed this would be a cheesy addition to the tour, but we loved it. We have visited many caves around the world with similar formations, so the train ride really made this one stand out from the rest!

When the train was built in 1872 it was the world’s first railway in a cave. Today it is still the world’s only double track railway in a cave! The train goes a bit faster than we expected, making it feel like we were on some sort of Disney ride. And along the way we got to see many of the cave’s formations. It was a great teaser of what’s to come!

Cave tour

Once the train stops at the station in the cave, you will follow your tour guide for the next hour the rest of the way through the cave.

Your tour guide will share facts and stories about the cave as you navigate on the paved path between the massive rooms. Some rooms have different names that describe what you’ll find there, like the spaghetti chamber, white chamber, and red chamber. Along the way, you’ll also get to see all kinds of formations, from curtains to stalactites and stalagmites. Many are hundreds of thousands of years old and are slowly, but surely growing over time.

You will also learn about the 115 different animals that call the cave home, with the most famous being olms. These are blind salamanders that are nicknamed “baby dragons,” due to the belief that they were offspring of a terrible dragon that lived in the cave, upon the discovery of them in the 17th century.

While not true, they are still pretty remarkable creatures! They have no eyes, can live up to 100 years, and go without any food for many years. Towards the end of the tour you’ll get to visit an aquarium, where some of them live!

Respect the cave! As you explore the cave, make sure to follow the rules to not only keep yourself safe, but keep the cave preserved for future visitors. This includes not walking off the marked path, not touching the stalactites and stalagmites, not taking photos with flash, and not smoking, littering, or bringing food into the cave.

Postojna’s Underground Post Office

Just like many tours, the guided part of the tour ends at a gift shop. But this gift shop is much more interesting than almost all gift shops we’ve come across. And that’s because there is also an underground post office attached!

According to the signage, this is the world’s only cave post office. So we couldn’t pass up a chance to send our family some postcards from deep underground.

After you’ve sent your mail and bought anything from the gift shop, it’s time to hop back on the train. The train out follows a different path, allowing you to see even more of the cave. But instead of dropping you off right at the end, you will get dropped off at the river that created the cave (which is super cool to see!) and walk the final 10 minutes back to the outside world.

Want a more adventurous tour?

If you want something a bit more adventurous, check out Postojna Cave’s adventure tours!

These special tours take you to parts of the cave that are closed off for regular tours. The “Trek Through Three Caves” tour doesn’t require special equipment and is suitable for most visitors. You can book this tour online for €90 and is only available in July and August.

But if you want something a bit more adrenaline pumping, check out the “In the Footsteps of Luka Čeč” tour. On this tour, you’ll be kitted out in caving boots, helmet, a rope, and headlamp as you venture into the depths of the cave.

With an experienced guide, your small group will negotiate challenging cave passages, experience darkness and silence, cross the Pivka River, and walk in the footsteps of early cave explorers. We personally think this looks awesome and would love to do it next time!

If interested in the “In the Footsteps of Luka Čeč” tour, send an email to info@postojnska-jama.eu. This tour is only available from May through September.

What to expect at Predjama Castle

Predjama Castle at a glance

Cost: €21 per adult (cheaper with combo ticket)
Total length of time: About 1 hour (but you can take as long as you’d like!)
Timeslot required?: You can freely show up at the castle at any time, no timeslot required.
Languages: The audio guide for Predjama Castle features 19 languages.
Difficulty: There are some stairs throughout the castle and cave, so if stairs are tough for you, it may be difficult. But overall it’s a very easy tour!

Once arriving at Predjama Castle you’ll almost instantly catch a glimpse of this one of a kind building. And if you only care to see the outside, you can just pay to park and snap some photos for free. But we recommend going in as well!

However, to fully appreciate what you see inside, you need to first download the audio guide onto your phone. (Make sure to pack headphones!) This guide walks you from room to room, telling you the story of the castle along the way. It makes the experience so much more interesting!

While inside you not only get beautiful views of the surrounding valley, but you can also see a wide variety of features and rooms, from the different defense mechanisms used, the torture chamber, a dining room, kitchen, armoury and attic, and even a bell that you can ring!

But our favorite part of the castle was getting to explore the cave that the castle is built into. This is towards the end of the tour, if following the audio guide, and truly blew us away! And if you want to further explore these caves, you can book a tour of the caves under the Predjama Castle. This tour is only offered from May-September and looks like a lot of fun!

Also, included in your ticket to Predjama Castle you can also visit the Stara Dama Museum. This small museum shares a bit about the area and its history through turbulent war times, plus an exhibit on hunting in the area.

A+K Tip: After you tour the cave and castle, make sure to grab lunch at Pizzerija Minutka. We LOVED their pizza, gnocchi with slow roasted beef, and their unique spin on an apple pie!

Frequently Asked Questions

Can you experience Postojna Cave without a guide?

No, you can only see Postojna Cave on a tour with a guide. You are able to explore Predjama Castle on your own. But we recommend downloading the audio guide on your phone!

What should you wear to visit Postojna Cave and Predjama Castle?

The temperature inside Postojna Cave is only 9ºC (48ºF), so make sure to bring a jacket! We also suggest wearing good shoes with grip, as some areas can be wet.

And for Predjama Castle, make sure to pack headphones for the audio guide!

Are these tours dog friendly?

Dogs are not allowed in the cave or castle. Postojna Cave does have free dog kennels you can leave your dog in during the tour.

When should you visit Postojna Cave and Predjama Castle?

Both Postojna Cave and Predjama Castle are open 365 days per year, including holidays, no matter the weather. So anytime is possible to visit! But if you want to do some of the more advanced tours or utilize the shuttle between the two attractions, we’d suggest visiting in the summer season.

The hours do vary by season, so make sure to check in advance to plan your visit!

Is Postojna Cave or Skocjan Cave better?

Before our visit to Slovenia, we debated if we should visit Postojna Cave or Škocjan Cave. Multiple people told us that they liked Škocjan Cave better, as it’s more of a wild, less touristy experience. And from the photos we have seen, it does look pretty epic!

Unfortunately we only had enough time for one cave. Since we planned to visit Predjama Castle as well, Postojna Cave made more sense for us. Plus, you cannot take photos or videos on the Škocjan Cave tour, which was a bit of a con for us, as we wanted to document the experience.

In the end, we are very happy with our choice. Postojna Cave, while a bit more commercial, is incredible–especially the train ride! We firmly believe you cannot go wrong with either, it just comes down to which experience appeals to you more.